The big problem of material handling equipment is that, when navigating with a slow speed (a forklift truck for instance may, according to the appropriate law, navigate with a maximum speed of 7 km/h in a warehouse and with a maximum speed of 11 km/h outside warehouses) inside and outside warehouses—wherein in warehouses mostly every available space is used for storage—impacts frequently take place. The consequence of these impacts is that they possibly lead to damage of the load transported by the material handling equipment, but even more severely possibly lead to injuring the driver of this material handling equipment, for instance by giving this driver a whiplash.
It is already known to provide the material handling equipment with sensors in order to warn the driver of the material handling equipment that he/she is approaching an obstacle.
The problem with these sensors however is that these constantly produce signals because the material handling equipment approaches obstacles to a distance of approximately 1 cm. In this way, these sensors do not function in the desired way.
In JP 2008297067 for instance, a rear bumper is disclosed which is provided with a linear pressure-sensitive sensor which is fixed to a buffer plate by means of a sensor support board, by which the rear bumper is capable of alerting existence of a forklift to a person around the forklift, and additionally is capable to detect contact with a person.
It is furthermore known to provide a forklift truck with a steel bumper in order to absorb the energy released when an impact takes place between the forklift truck and an obstacle.
The disadvantage thereof however is that when a collision has taken place, the bumper remains deformed, finally leading to a non-usable bumper.
In GB 2418660, an impact absorbing device is disclosed which is provided to be mounted on the load back rest of a fork lift truck to reduce or eliminate damage to the load caused by impacts between the load and the load back rest during loading and transportation. The impact absorbing device therefore comprises an elongate body of rubber or the like, either hollow or solid and being mounted on the load back rest such that the load rested on the load back rest will contact the impact absorbing device first.
This impact absorbing device however only serves to protect the load from damage from an impact between the load back rest of the fork lift truck and the load, but cannot at all be used as an impact deceleration device serving to protect the load and/or the driver of the material handling equipment from an impact caused by a collision with an obstacle.
It is an object of the present invention to provide a material handling equipment impact deceleration device which is able to reduce the danger of shocks caused by a light impact imposed to the driver of the material handling equipment and/or the load transported by the material handling equipment when colliding with an obstacle at a lower speed with a maximum of 7 to 8 km/h, as well as when colliding with obstacles at a slightly higher speed of 10-11 km/h, leading to heavier shocks imposed to the driver of the material handling equipment and/or the load transported therewith.
The material handling equipment impact deceleration device consequently has to be able to decrease as much as possible the deceleration of the material handling equipment (expressed in m/s2) at impact between the material handling equipment and an obstacle on a short distance (because it is this deceleration which serves as the parameter in order to reduce the injuries of the driver of the material handling equipment or to reduce the impact of collisions between the material handling equipment and an obstacle on the load carried by the material handling equipment), and this while keeping the dimensions of the material handling equipment impact deceleration device as small as possible.
It is a further object of the invention to provide a material handling equipment impact deceleration device which does not permanently deform when collisions at a lower speed takes place.